Locking mechanism

ABSTRACT

A crank centrally located on a desk has an opening in its offset portion engaged by a pin eccentrically mounted on a tumbler lock to translate the rotational motion of the lock directly to rotational motion of a shaft on which the crank is mounted. The shaft extends to either side of the crank to actuate other locking means on each side thereof.

[ Dec. 4, 1973 United States Patent 1 1 Himsl FOREIGN PATENTS OR APPLICATIONS LOCKING MECHANISM 2,218,683 10 1940 um [75] Inventor: Ernst G. Rims, Kitchener, Ontario, 2,225,243 12/1940 Znttel Canada [73] Assignee: Massey-Ferguson Industries Limited,

Toronto, Ontario, Canada Primary Examiner-Robert L. Wolfe [22] Flled' Sept. 1972 AttorneyGeorge C. Bower Appl. No; 287,148

ABSTRACT 52 us. 7o 86, 292 21 312 21 {51% 1111. E 05b 6 5/42 A rank centrally mated a desk has Penmg m its offset portion engaged by a pin eccentrically 58 F Id Sear l 1 le 0 c mounted on a tumbler lock to translate the rotational 2/ 9 I l l 9 4 7 DI 5 motlon of the lock d1rectly to rotat1ona1 mot1on of a 1 shaft on which the crank is mounted. The shaft ex- [56] References Cited UNITED STATES PATENTS 292/215 6 Claims, 3 Drawing Figures PATENTEDUEC 4197a I 3,776,007

sum 1 [IF 2 LOCKING MECHANISM Heretofore it has been known to provide for the locking of side pedestal drawers of a desk using a centrally located lock. US. Pat. No. 2,793,927 issued to C. R. Reitzel on May 28, 1957 illustrates such a locking system in FIG. 1 whereby a tumbler type lock actuates'a tongue having straight line motion to engage an eccentric arm with a wedge-shaped cam mounted on the tongue. Thus, the rotational motion of the lock is translated into straight line motion of the tongue and then into rotational movement of the eccentric arm. The eccentric arm actuates a shaft and the rocker armthereon which raises and lowers a lock bar on which is mounted a striker for engaging a side drawer to lock it in position. The parting line between the cam and the eccentric arm permits movement of the lock assembly, which while still being capable of disengaging the lock from the actuator for the shaft. The result is a simpler more compact mechanism requiring less space and material. Further the action of the mechanism ispositive in both the locking and unlocking directions wherein there is continuous contact between the actuator on the shaft with that on the lock. I

The present invention relates to locking mechanisms and more particularly to mechanisms centrally located on furniture for locking drawers on either side thereof having a drawer slidably disposed on the furniture and a locking bar sliding adjacent the drawer to enable a striker on the bar to engage the drawer upon travel of the bar in one direction thereby preventing the drawer from sliding. The locking bar is eccentrically attached to a rotating shaft. The locking mechanism includes key controlled means such as a tumbler lock having an engagingmember on it which may be an eccentrically mounted pin. An eccentric member is affixed to the rotating shaft to rotate it upon rotation of the pin on the lock. The pin moves withina recess in the eccentric member, which may be a crank, tothereby slide the locking bar and lock the drawer.

The above mechanism results in a compact and simpler design resulting in economic savings over devices of theprior art.

FIG. 1 is a perspective view of apparatus incorporating the present invention and a fragmentary part of subordinate desk drawers illustrated in phantom;

FIG. 2 is an enlarged top view of a portion of the apparatus illustrated in FIG. 1; and

FIG. 3 is a crosssectional view of the apparatus illustrated in FIG. 2 taken along line 3--3 thereof.

Referring to FIG. 1, there is illustrated a locking mechanism on a rotating shaft 12 being centrally located with the shaft 12 extending from either side of the locking mechanism 10. Typically, when the locking contains drawers 16, as illustrated in phantom. A rocker arm 18 is affixed to the shaft 12 and eccentrically supports a locking bar 20 attached thereto with a screw 22. In a double pedestal desk the above structure is duplicated for the other pedestal forming the symmetrical structure illustrated in FIG. 1. V

The locking bar 20 may be provided with a box member 24, incorporated within the side 26 of the pedestal, in which the locking bar 20 is permitted to travel. On the inner face 28 of the box member 24 there are a plurality of slots 30 through which a plurality of strikers 32 pass and are affixed to the locking bar 20. The slots 30 have their lengths aligned with the length of the locking bar 20 to permit the strikers 32 to travel therein.

In the locked position, illustrated in FIG. 1, the striker 32 is at one end of the slot 30. Upon travel of the locking bar by rotation of the shaft 12, the striker,

32 is moved to the other end of the slot 30 in which position means on the drawer 16 are disengaged to permit the drawer 16 to slide relative to the pedestal.

Thus, thelocking mechanism 10 is capable of locking all the side drawers 16 of the pedestals from a single central location. It will be noted that the shaft 12 is adjustable to accommodate various desk sizes as well as other furniture by varying its length. Adjustment of the length of the shaft 12 is accomplished by loosening the set screw 34 on a sleeve portion 36 of the shaft 12 and sliding the rod portion 38 either in or out to decrease or increase the length of the shaft 12 respectively.

FIGS. 2 and 3 illustrate the locking mechanism in greater detail wherein the center panel 14 has affixed to it a U bracket with an opening 52 in its base 54 for receiving a tumbler assembly 56 of a lock 58. The lock 58 has a head 60 for receiving a key (not illustrated) in a slot 62 thereon. The key rotates the tumbler assembly 56 in the usual manner. The head 60 is mechanism 10 is used in a pedestal type desk, a center panel 14 beneath the top of the desk provides support for the locking mechanism 10 in a centrally mounted biger than the opening 52 and acts like a bolt head when a nut 64 is screwed on over the threaded tumbler assembly 56 to fasten the bracket 50 to the center plate 14. Attached to a rotatable portion 66 of the tumbler assembly 56 is a cylinder 68 having an eccentrically mounted pin 70 thereon.

The pin 70 acts as an engaging member with a recess, in the form of an elongate hole 72, in an eccentric member such as the crank 74. The cylinder 68 and pin 70 could be replaced with a crank with one end at tached to the rotatable portion 66 of the tumbler assembly 56 and the other end being the engaging membet, and the recess need not be a hole 72. One skilled in the art will be aware of other modifications which could be made to obtain a suitable engaging member and corresponding recess.

The elongate hole 72 is oriented parallel to the axis of the shaft 12.being located in the offset portion 76 of the crank 74. The elongate hole 72 accommodates the arcuate motion of the pin 70, when the rotatable portion 66 of the lock 58 is rotated through by permitting the pin 70 to travel approximately the length of the hole 72. At the same time, the arcuate motion of the pin 70 moves in a plane normal to both the axis of rotation of the shaft 12 and the axis of rotation of the lock 58 causing clockwise rotation of the crank 74 about the shaft 12. Another 90 of rotation of thepin 70 causes further clockwise rotation of the crank 74 about the shaft 12 while the pin 70 returns across the length of the hole 72. A travel of by the pin 70 causes 90 of rotation by the crank 74 to move the shaft 12 from the locked position illustrated to the unlocked position (as illustrated in phantom in FIG. 3).

Thus, the rotational motion of the lock 58 is translated directly into rotational motion of the shaft 12, which is at right angles to the lock, and maintains positive engagement between the pin 70 and the crank 74 throughout the motion.

It is to be understood that modifications could be made to the lock mechanism to permit its use with a center drawer type desk by mounting the lock 58 in the center drawer and placing the U bracket 50 or like type support on the desk proper and having the pin engage and disengage the crank 74 upon closing and opening the center drawer.

In the embodiment illustrated, the crank 74 is not disengaged by the lock 58 because it is pivotally mounted on the legs 78 of the bracket 50. Bearings 80 are pressed into suitable. openings 82 in the legs 78 and support an interconnecting rod 84. The interconnecting rod 84 has a flat 86 against which set screws 88 bare to prevent disengagement of the sleeve 36 from the interconnecting rod 84. The set screws 88 further militate against rotation between the interconnecting rod 84 and the sleeve 36. One of the set screws 88 is mounted on each end of the crank 74 in concentric receivers 90 having bores 92 therein for receiving the interconnecting rod 84.

FIG. 3 illustrates a cross-sectional profile of the crank 74 and the flush mating surfaces 94 which engage the pin 70 in the locked position in a deadlock manner to prevent the pin from being rotated by forces applied to the crank 74 through the linkage connected to the pedestal. The same condition exists in the unlocked position (illustrated in phantom), but with mating surfaces 96 engaging the pin 70, to prevent the drawers from being locked by forces on the strikers 32,

ber used.

In accordance with the provisions of the patent statutes, the principle and mode of operation of the apparatus have been explained and what is considered to represent its best embodiment has been illustrated and described. It should, however, be understood that the invention may be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.

I claim:

1. In an article of furniture having a drawer slidably disposed in a housing in which a locking bar slides to enable a striker on the bar to engage the drawer upon travel of the locking bar in one direction to prevent the drawer from sliding,'the locking bar being attached eccentrically to a rotating shaft, a locking mechanism comprising, key controlled means, an engaging member on said key controlled means, and an eccentric member having a recess therein, said eccentric member affixed to the rotating shaft to rotate the shaft upon rotation of said engaging member on said key controlled means within the recess in said eccentric member to thereby slide the locking bar and lock the drawer.

2. The combination defined in claim 1 wherein said eccentric member includes a crank having an offset portion.

3. The combination defined in claim 2 wherein the.

recess in said eccentric member is located in saidoffset portion of said crank.

4. The combination defined in claim 1 wherein said the locked or unlocked position. 

1. In an article of furniture having a drawer slidably disposed in a housing in which a locking bar slides to enable a striker on the bar to engage the drawer upon travel of the locking bar in one direction to prevent the drawer from sliding, the locking bar being attached eccentrically to a rotating shaft, a locking mechanism comprising, key controlled means, an engaging member on said key controlled means, and an eccentric member having a recess therein, said eccentric member affixed to the rotating shaft to rotate the shaft upon rotation of said engaging member on said key controlled means within the recess in said eccentric member to thereby slide the locking bar and lock the drawer.
 2. The combination defined in claim 1 wherein said eccentric member includes a crank having an offset portion.
 3. The combination defined in claim 2 wherein the recess in said eccentric member is located in said offset portion of said crank.
 4. The combination defined in claim 1 wherein said recess is elongate in a direction paralleling the rotating shaft to enable said engaging member to slide in said recess causing movement of said eccentric member.
 5. The combination defined in claim 1 wherein said key controlled means includes a lock with a tumbler assembly upon which said engaging member is eccentrically mounted.
 6. The combination defined in claim 1 wherein said eccentric member includes mating surfaces within the recess therein for contacting said engaging member in a deadloCk manner when said eccentric member is in the locked or unlocked position. 